Cost of Living in Lusaka

Lusaka is a bustling city full of surprises if you look. The downside is rent is on the pricey side than say what you would expect to pay in most places in SEA. You can find some low rental places but then you'd be putting yourself in an environment that's not particularly safe. I'd pick a neighbourhood like Kabulonga, Woodlands, Chilenje, Ibex Hill or Makeni. Getting around is easier if you have a car or find a reliable cabby. You can also use the local rideshare app called Ulendo Taxi, it works well and even has female drivers, which I think is great for solo female travellers.
Public safety is okay, best not to travel to compounds where safety can be a major issue, especially if you're a muzungu, a local word for 'White person' or someone considered well-off. Expect to be crowded around by street vendors selling everything from phone accessories, clothing, and sometimes local crafts. I wouldn't advise purchasing from these as you'll get ripped off - best go to the weekend markets or the craft village.
Zambia doesn't have a café or coffee culture per se but you can find some pretty decent coffee shops that have great coffee and free wifi. Zam Bean Coffee, The Corner Café and 3Tree's are my favs. I'd advise to join the Expat Group's on Facebook for more tips and questions.